This invention relates to an adaptive cruise control system for a vehicle.
It is well known to provide automatic vehicle cruise control systems for maintaining the speed of a vehicle at an operator-set speed. It is further known to provide, in conjunction with these known cruise systems, a system for detecting the presence and the distance to a preceding vehicle and for adjusting the vehicle speed to maintain a trailing distance to the preceding vehicle. In essence, the vehicle speed is controlled to the speed of the preceding vehicle with a predetermined separation from the preceding vehicle with the vehicle speed being limited at the operator-set cruise speed.
Typically, the trailing distance provided by these known systems is a predetermined calibrated value or schedule of values as a function of parameters such as vehicle speed. These calibration values generally do not take into account varying traffic conditions, weather conditions, road surface conditions or personal driving habits of the vehicle operator. The calibrated values are accordingly a compromise that may be optimum for one operator and for a specific set of weather/road/traffic conditions but may not be optimum for different operators and varying conditions.